申请人:Ricoh Company, Ltd.
公开号:US05084593A1
公开(公告)日:1992-01-28
Leuco dyes of the formula (I) are disclosed, ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 each represent an alkyl group having 1 to 10 carbon atoms; X represents hydrogen, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms or a halogen; and Y represents R.sub.5 --Z--SO.sub.2 NH--, R.sub.6 --Z--CONH--, or ##STR2## in which Z represents ##STR3## R.sub.5 and R.sub.6 each represent hydrogen, an alkyl group having 1 to 10 carbon atoms, or a halogen; and R.sub.7 and R.sub.8 each represent hydrogen, a cyano group, or --COR.sub.9, in which R.sub.9 represents a lower alkyl group, a lower alkoxyl group, a phenyl group which may be substituted by an alkyl group having 1 to 4 carbon atoms, an alkoxyl group having 1 to 4 carbon atoms, or a halogen; a naphthyl group which may be substituted by an alkyl group having 1 to 4 carbon atoms, an alkoxyl group having 1 to 4 carbon atoms or a halogen with the proviso that R.sub.7 and R.sub.8 are not both hydrogen. Further a recording material comprising any of the above-mentioned leuco dyes and a particular phenolic compound as a color developer capable of inducing color formation in the leuco dye is disclosed.
公开了式(I)的白色染料,其中R1,R2,R3和R4分别表示具有1至10个碳原子的烷基基团;X表示氢,具有1至10个碳原子的烷基基团,具有1至10个碳原子的烷氧基或卤素;Y表示R5-Z-SO2NH-,R6-Z-CONH-或的任何一种,其中Z表示,R5和R6分别表示氢,具有1至10个碳原子的烷基基团或卤素;R7和R8分别表示氢,氰基或-COR9,其中R9表示较低的烷基基团,较低的烷氧基团,苯基,该苯基可以被具有1至4个碳原子的烷基基团,具有1至4个碳原子的烷氧基或卤素替代;萘基,该萘基可以被具有1至4个碳原子的烷基基团,具有1至4个碳原子的烷氧基或卤素替代,但R7和R8不能同时为氢。此外,还公开了包含上述任何白色染料和特定酚类化合物作为彩色显影剂的记录材料,该彩色显影剂能够引起白色染料的颜色形成。